No longer lobs off a limb

Very sad.

I think it's still pretty strong, but limb body chunk loss that was entirely up to the DM to adjudicate was really annoying to keep track of and come up with mechanics for.

Hmm. A very rare weapon only useful 5% of the time and it takes up an attunement slot. On average a 1+ weapon is more useful in my opinion (remind you no attunement needed for an uncommon sword). The exhaustion is useful by giving the target -2 to all d20 rolls and reduces its speed by 5. I doubt you would roll two 20s in a single combat although its possible to stack that penalty. Sure, you deal on average 2-4 more damage per attack against an object but I have never been in a situation where that additional few points of damage makes a significant difference. I could see this being a very rare magical item if it had at least a 1+ bonus to attack and damage. All day any day would take a 2+ weapon over this. 

Quote from Crglaze >>

Hmm. A very rare weapon only useful 5% of the time and it takes up an attunement slot. On average a 1+ weapon is more useful in my opinion (remind you no attunement needed for an uncommon sword). The exhaustion is useful by giving the target -2 to all d20 rolls and reduces its speed by 5. I doubt you would roll two 20s in a single combat although its possible to stack that penalty. Sure, you deal on average 2-4 more damage per attack against an object but I have never been in a situation where that additional few points of damage makes a significant difference. I could see this being a very rare magical item if it had at least a 1+ bonus to attack and damage. All day any day would take a 2+ weapon over this. 

It's useful on every hit.  What do you mean only 5% of the time?  The benefit to criticals is not the main attraction here, though it is nice.

For a glaive, you deal 4.5 more damage per hit.  (Average of 1d10 is 5.5, max is 10.)

For a greatsword, it's 5 more damage per hit.  (Average of 2d6 is 7, max is 12.  Also, since it uses two dice, you are much less likely to get the max from rolling dice on greatsword than with single-die weapons.)

For a longsword, it's 3.5 if one-handed, 4.5 if two.  For a scimitar it's 2.5 (but of course, since it is light, it enables dual-wielding, so you get more opportunities for hits per turn).

So, your math is off there, to begin with.  And extra damage to EVERY hit is HUGE.

Whether or how much it outweighs a +1 or +2 depends on the opponent's AC and what your adds are otherwise.  But let's take the case of an AC of 15, and base adds of +7 from proficiency and ability modifier (let's say +3 and +4, respectively), and compare a longsword of sharpness to a +2 longsword (wielded one-handed).  With a +2 longsword on top of a base +7 for a total of +9, you have a 75% chance of hitting AC 15 for 1d8+6 (+2 from sword, +4 from ability mod), or an average of 10.5 damage per hit.  10.5 * 0.75 = 7.875 average damage per attack roll.

With a longsword of sharpness, your +7 to hit gives you a 65% change to hit the same AC, and you deal 12 damage every time you hit.  12 * 0.65 = 9 average damage per attack roll.

So, in that scenario, at least (which I deliberately chose to be squarely in the typical range), the sword of sharpness gives a higher DPR.  14% higher.

I have made a simplification here in not considering criticals, but since a +2 sword doesn't make criticals any more likely, and criticals with a sword of sharpness are stronger (14 extra damage!  huge), considering criticals would only tilt the analysis more in favor of the sword of sharpness.